The degradation of chondroitin 4-sulfate by enzymes of the gastric mucosa is being studied. It appears that a concerted action by a sulfatase, an N-acetylgalactosaminidase and a beta-glucuronidase are involved. Purification of the sulfatase will be undertaken, quided by the principle that extensive desulfation by even a highly purified sulfatase will require the addition (or back-addition) of the exoglycosidases.